Agricultural machinery, such as silage cutters, are pulled behind a tractor. An associated collector vehicle is coupled behind the silage cutter with a crop discharge spout on the silage cutter discharging crop into the associated collector vehicle. When the tractor turns a corner, however, the crop discharge spout on the silage cutter swings away from the associated collector vehicle and crop is lost. There is, therefore, a need for an apparatus for controlling the direction of the crop discharge spout.
A mechanical system for controlling the direction of the crop discharge spout was disclosed in U.S. Pat. No. 2,905,343 which issued to Deere & Company in 1959. This mechanical system included a rigid substantially upright standard having a first end secured to the discharge spout and a second end secured to a clevis style hitch on a drawbar on the associated collector vehicle. The rigid standard caused the discharge spout to swivel in unison with the lateral swinging of the drawbar. The mechanical system, as described, always had the discharge spout aimed at the center of the collector vehicle. It was not possible to maximize the load by directing crop discharge from the discharge spout into the corners of the collector vehicle. It was, similarly, not possible to swing the discharge spout sideways to load an adjacent collector vehicle. An elaborate support structure had to be incorporated into the design to prevent downward deflection of the drawbar as the rigid standard was incapable of withstanding such movement.
An alternative system adopted, as described as background in U.S. Pat. No. 3,786,945 which issued to Deere & Company in 1974 involved equipping the discharge spout with a worm and worm wheel arrangement with an elongate crank arm extending to within reach of the operator. In negotiating a corner, the operator would turn the crank to rotate the worm to laterally turn the spout. This system was considered unsafe as the operator had to look back and observe the spout to assure proper positioning while the tractor was moving forward.
At the present time the art has moved away from mechanical apparatus for controlling the direction of a crop discharge spout in favor of more sophisticated electronic systems as described in U.S. Pat. Nos. 3,786,945; 4,042,132; 4,376,609; and 4,441,846.